share/colnew/fortran/horder.f

   1       SUBROUTINE HORDER (I, UHIGH, HI, DMZ, NCOMP, K)
   2 C
   3 C**********************************************************************
   4 C
   5 C   purpose
   6 C           determine highest order (piecewise constant) derivatives
   7 C           of the current collocation solution
   8 C
   9 C   variables
  10 C     hi     - the stepsize, hi = xi(i+1) - xi(i)
  11 C     dmz    - vector of mj-th derivative of the solution
  12 C     uhigh  - the array of highest order (piecewise constant)
  13 C              derivatives of the approximate solution on
  14 C              (xi(i),xi(i+1)), viz,
  15 C                          (k+mj-1)
  16 C              uhigh(j) = u   (x)    on (xi(i),xi(i+1))
  17 C                          j
  18 C
  19 C**********************************************************************
  20 C
  21       IMPLICIT REAL*8 (A-H,O-Z)
  22       DIMENSION UHIGH(1), DMZ(1)
  23 C
  24       COMMON /COLLOC/ RHO(7), COEF(49)
  25 C
  26       DN = 1.D0 / HI**(K-1)
  27 C
  28 C...  loop over the ncomp solution components
  29 C
  30       DO 10 ID = 1, NCOMP
  31          UHIGH(ID) = 0.D0
  32    10 CONTINUE
  33       KIN = 1
  34       IDMZ = (I-1) * K * NCOMP + 1
  35       DO 30 J = 1, K
  36          FACT = DN * COEF(KIN)
  37          DO 20 ID = 1, NCOMP
  38             UHIGH(ID) = UHIGH(ID)  +  FACT * DMZ(IDMZ)
  39             IDMZ = IDMZ + 1
  40    20    CONTINUE
  41          KIN = KIN + K
  42    30 CONTINUE
  43       RETURN
  44       END